Method and apparatus for registration of information with plural institutions and recording medium with registration program stored thereon

Abstract

A user 300 generates a cipher key EK and pieces of information I A and I B , and sends information EK(I B ), obtained by enciphering the information I B with the cipher key EK, and the information I A to an institution 100 . The institution 100 registers the information I A as information of the user 300 , and sends the information EK(I B ) to an institution 200 . The institution 200 enciphers its received information EK(I B ) with the cipher key EK to obtain the information I B and registers the deciphered information I B .

What is claimed is:  
     
         1 . A method by which a user registers different pieces of information with institutions A and B, respectively, said method comprising the steps wherein: 
 (a) said user generates pieces of information I A  and I B  to be registered with said institutions A and B, respectively;    (b) said user enciphers said information I B  with an encipher key EK to obtain enciphered information EK(I B ), and sends said information I A  and said enciphered information EK(I B ) to said institution A;    (c) said institution A registers said information I A  as information corresponding to the real name of said user, and sends said information EK(I B ) to said institution B; and    (d) said institution B deciphers said information EK(I B ) with a decipher key DK to obtain said information I B , and registers it.    
     
     
         2 . The method of  claim 1 , which further comprises a step wherein said institution B pregenerates a public key PK B  and a secret key SK B  as said encipher key EK and said decipher key, respectively, and provides said public key PK B  to said user, and in which: 
 said step (b) is a step of enciphering said information I B  with said public key PK B  used as said encipher key EK to obtain information PK B (I B ) as said information EK(I B ) and sending it as said information EK(I B ) to said institution A, together with said information I A ;    said step (c) includes a step of sending said information PK B (I B ) as said information EK(I B ) to said institution B; and    said step (d) includes a step of deciphering said information PK B (I B ) with said secret key SK B  used as said decipher key DK to obtain said information I B .    
     
     
         3 . The method of  claim 1 , which further comprises a step wherein said institution B pregenerates a public key PK B  and a secret key SK B  and provides said public key PK B  to said user, and in which: 
 said step (b) includes a step of generating a common cipher key K as said encipher key EK, enciphering said information I B  with said common cipher key K to obtain information K(I B ) as said information EK(I B ), enciphering said common cipher key K with said public key PK B  to obtain information PK B (K), and sending said pieces of information K(I B ) and PK B (K) as said information EK(I B ) to said institution A, together with said information I A ;    said step (c) includes a step of sending said pieces of information K(I B ) and PK B (K) as said information EK(I B ) to said institution B; and    said step (d) includes, as a process for deciphering said information DK(I B ) with said decipher key DK, a step of deciphering said information PK B (K) with said secret key SK B  to obtain said common cipher key K and deciphering said information K(I B ) with said common cipher key K to obtain said information I B .    
     
     
         4 . The method of  claim 3 , which further comprises a step wherein said institution A pregenerates a public key PK A  and a secret key SK A  and making said public key PK A  public, and in which: 
 said step (c) includes a step of generating a signature SK A (K (I B )) of said institution A for said information K (I B ) contained in information received from said user apparatus, and sending said signature SK A (K (I B )) to said institution B, together with said pieces of information PK B (K) and K(I B ); and    said step (d) includes a step of verifying, with said public key PK A , the validity of said signature SK A (K(I B )) in information received from said institution A and, if said signature is found valid, deciphering said information PK B (K).    
     
     
         5 . The method of  claim 1 , which further comprises a step wherein said institution B pregenerates a public key PK B  and a secret key SK B  as said encipher key EK and said decipher key DK, and provides said public key PK B  to said user, and in which: 
 said step (b) includes a step of generating a common cipher key K, enciphering said information I B  and said common cipher key K with said public key PK B  used as said encipher key EK to obtain information PK B (I B , K) as said information EK(I B ), and sending said information PK B (I B , K) to said institution A, together with said information I A ;    said step (c) includes a step of registering said pieces of information I A  and PK B (I B ,K) received from said user, as information corresponding to the real name of said user, and sending said information PK B (I B , K) as said information EK(I B ) to said institution B; and    said step (d) includes a step of deciphering, with said secret key SK B , said information PK B (I B , K) in information received from said institution A to obtain said information I B  and said common cipher key K and registering at least said information I B .    
     
     
         6 . The method of  claim 2  or  5 , which further comprises a step wherein: 
 said institution A pregenerates a public key PK A  and a secret key SK A ;  
 said institution A generates, with said secret key SK A , its signature for information enciphered with said public key PK B , contained in information received from said user, and also sends said signature to said institution B; and  
 said institution B verifies, with said public key PK A , said signature in information received from said institution A and, if said signature is found valid, deciphers, with said secret key SK B , said information enciphered with said public key PK B .  
 
     
     
         7 . The method of  claim 3 ,  4 , or  5 , which further comprises the steps wherein: 
 said institution B:    (1) registers said deciphered said common cipher key K together with said information I B ;    (2) generates a digital signature SK B (I B ) for said information I B  through the use of said secret key SK B ;    (3) generating information K(SK B (I B )) by enciphering said digital signature SK B (I B ) with said common cipher key K;    (4) generating a signature SK B (K(SK B (I B ))) of said institution B for said information K(SK B (I B )); and    (5) sends said information K(SK B (I B )) and said signature SK B (K(SK B (I B ))) therefor to said institution A;    said institution A:    (6) verifies the validity of said signature SK B (K(SK B (I B ))) in information received from said institution B, through the use of said public key PK B ;    (7) if said signature SK B (K(SK B (I B ))) is found valid, generates a digital signature SK A (I A ) for said information I A ; and    (8) sends said digital signature SK A (I A ) and said information K(SK B (I B )) received from said institution B to said user; and    said user:    (9) deciphers said information K(SK B (I B )) in information received from said institution A through the use of said common cipher key, thereby obtaining said digital signature SK B (I B ); and    (10) verifies the validity of said signatures SK A (I A ) and SK B (I B ) and, if they are both found valid, recognizes that said pieces of information I A  and I B  have been registered with said institution A and said institution B, respectively.    
     
     
         8 . The method of  3 ,  4 , or  5 , wherein said institution A also registers information containing said information I B  in said information received from said user.  
     
     
         9 . The method of  claim 3 ,  4 , or  5 , which further comprises the steps wherein: 
 said institution B:    (1) registers said deciphered common cipher key K together with said information I B ;    (2) generates a digital signature SK B (I B ) for said information I B  through the use of said secret key SK B ;    (3) enciphers said digital signature SK B (I B ) with said common cipher key K, thereby obtaining information K(SK B (I B )); and    (4) sends said information K(SK B (I B )) to said institution A;    said institution A:    (5) sends said information K(SK B (I B )) received from said institution B to said user; and    said user:    (7) deciphers said information K(SK B (I B )) from said institution A with said common cipher key K, thereby obtaining said digital signature SK B (I B ) of said institution B for said information I B ; and    (8) verifies the validity of said digital signature SK I (I B ) with said public key PK B  and, if said digital signature SK B (I B ) is found valid, recognizes that said information I B  has been registered with said institution B.    
     
     
         10 . A user apparatus in a system in which a user registers different pieces of information I A  and I B  with institutions A and B, respectively, said user apparatus comprising: 
 a memory for storing a public key PK B  of said institution B;    common key generating means for generating a common cipher key K and for storing it in said memory;    information generating means for generating said information I A  for registration with said institution A and said information I B  for registration with said institution B and for storing said pieces of information I A  and I B  in said memory;    encipher means for enciphering said information I B  and said common cipher key K with said public key PK B  to generate information PK B (I B , K);    means for sending said information PK B (I B , K) and said information I A  to said institution A;    decipher means for deciphering information K(SK B (I B )) received from said institution A to obtain a signature SK B (I B ); and    signature verification means for verifying the validity of said signature SK B (I B ) with said public key PK B  and said information I B .    
     
     
         11 . A user apparatus in a system in which a user registers different pieces of information I A  and I B  with institutions A and B, respectively, said user apparatus comprising: 
 a memory for storing a public key PK B  of said institution B;    common key generating means for generating a common cipher key K and for storing it in said memory;    information generating means for generating said information I A  for registration with said institution A and said information I B  for registration with said institution B and for storing said pieces of information I A  and I B  in said memory;    first encipher means for enciphering said common cipher key K with said public key PK B  to generate information PK B (K);    second encipher means for enciphering said information I B  with said common cipher key K to generate information K(I B );    means for sending said pieces of information PK B (K), K(I B ) and I A  to said institution A;    decipher means for deciphering information K(SK B (I B )) received from said institution A to obtain a signature SK B (I B ); and    signature verification means for verifying the validity of said signature SK B (I B ) with said public key PK B  and said information I B .    
     
     
         12 . The user apparatus of  claim 10  or  11 , wherein said memory has held therein a public key PK A  of said institution A and said signature verification means includes means for verifying the validity of a signature SK A (I A ) received from said institution A through the use of said public key PK A  and said information I A .  
     
     
         13 . An institution A apparatus in a system in which a user registers different pieces of information I A  and I B  with institutions A and B, respectively, said institution A apparatus comprising: 
 a memory for storing a public key PK B  of said institution B;    means for storing in said memory said information I A  and information PK B (I B ) received from said user;    means for sending said information PK B (I B , K) to said institution B; and    means for sending information K(SK B (I B )) received from said institution B to said user.    
     
     
         14 . An institution A apparatus in a system in which a user registers different pieces of information with institutions A and B, respectively, said institution A apparatus comprising: 
 a memory for storing a public key PK B  of said institution B;    means for storing in said memory said information I A  and pieces of information K(I B ) and PK B (K) received from said user;    means for sending said pieces of information PK B (K) and K(I B ) received from said user to said institution B; and    means for sending information K(SK B (I B )) received from said institution B to said user.    
     
     
         15 . The institution A apparatus of  claim 13 , wherein said memory has held therein a secret key SK A  and a public key PK A  of said institution A, which further comprises signing means for signing said information PK B (I B , K) received from said user through the use of said secret key SK A  to thereby obtain signature information SK A (PK B (I B , K)), and wherein said sending means sends said signature information SK A (PK B (I B , K)) to said institution B together with said information PK B (I B , K).  
     
     
         16 . The institution A apparatus of  claim 14 , wherein said memory has held therein a secret key SK A  and a public key PK A  of said institution A, which further comprises signing means for signing said information K(I B ) received from said user through the use of said secret key SK A  to thereby obtain signature information SK A (K(I B )), and wherein said sending means sends said signature information SK A (K(I B )) to said institution B together with said pieces of information K(I B ) and PK B (K).  
     
     
         17 . The institution A apparatus of  claim 13 ,  14 ,  15  or  16 , which further comprises signature verification means for verifying, through the use of said public key PK B , the validity of each of said information K(SK B (I B )) and its signature SK B (K(SK B (I B ))) received from said institution B.  
     
     
         18 . The institution A apparatus of  claim 13 ,  14 ,  15  or  16 , which further comprises signing means for signing said information I A  in said memory with said secret key SK B  to thereby generate a signature SK A (I A ), said signature SK A (I A ) being sent to said user together with said information K(SK B (I B )) received from said institution B.  
     
     
         19 . An institution B apparatus in a system in which a user registers different pieces of information I A  and I B  with institutions A and B, respectively, said institution B apparatus comprising: 
 a memory for storing secret and public keys SK B  and PK B  of said institution B;    decipher means for deciphering information PK B (I B , K) from said institution A with said secret key SK B  and for storing the deciphered information I B  and common cipher key K in said memory;    signing means for signing information I B  in said memory with said secret key SK B  to obtain a signature SK B (I B );    encipher means for enciphering said signature SK B (I B ) with said common cipher key K to generate information K(SK B (I B )); and    means for sending said information K(SK B (I B )) to said institution A.    
     
     
         20 . An institution B apparatus in a system in which a user registers different pieces of information I A  and I B  with institutions A and B, respectively, said institution B apparatus comprising: 
 a memory for storing secret and public keys SK B  and PK B  of said institution B;    first decipher means for deciphering information PK B (K) from said institution A with said secret key SK B  to obtain a common cipher key K;    second decipher means for deciphering information K(I B ) from said institution A with said common cipher key K;    means for storing said deciphered information I B  and said common cipher key K in said memory;    signing means for signing said information I B  in said memory with said secret key SK B  to obtain a signature SK B (I B );    encipher means for enciphering said signature SK B (I B ) with said common cipher key K to generate information K(SK B (I B )); and    means for sending said information K(SK B (I B )) to said institution A.    
     
     
         21 . The institution B apparatus of  claim 19  or  20 , which further comprises signing means for signing said information K(SK B (I B )) with said secret key SK B  to generate signature information SK B (K(SK B (I B ))), said signature information SK B (K(SK B (I B ))) being sent to said institution A together with said information K(SK B (I B )).  
     
     
         22 . A recording medium having recorded thereon a program for execution by a computer of a user apparatus in a system in which a user registers different pieces of information I A  and I B  with institutions A and B, respectively, said program comprising the steps of: 
 generating a common cipher key K;    generating said information I A  for registration with said institution A and said information I B  for registration with said institution B;    storing said common cipher key K and said pieces of information I A  and I B  in a memory;    enciphering said information I B  and said common cipher key K with a public key PK B  of said institution B to obtain information PK B (I B , K);    sending said pieces of information I A  and PK B (I B , K) to said institution A;    deciphering information K(SK B (I B )) from said institution A with said common cipher key K to obtain a signature SK B (I B ); and    verifying the validity of said deciphered signature SK B (I B ) with said public key PK B  and said information I B .    
     
     
         23 . A recording medium having recorded thereon a program for execution by a computer of a user apparatus in a system in which a user registers different pieces of information I A  and I B  with institutions A and B, respectively, said program comprising the steps of: 
 generating a common cipher key K;    generating said information I A  for registration with said institution A and said information I B  for registration with said institution B;    storing said common cipher key K and said pieces of information I A  and I B  in a memory;    enciphering said common cipher key K with a public key PK B  of said institution B to generate information PK B (K);    enciphering said information I B  with said common cipher key K to obtain information K(I B );    sending said pieces of information I A , PK B (K) and K(I B ) to said institution A;    deciphering information K(SK B (I B )) from said institution A with said common cipher key K to obtain a signature SK B (I B ); and    verifying the validity of said deciphered signature SK B (I B ) with said public key PK B  and said information I B .    
     
     
         24 . The recording medium according to  claim 22  or  23 , wherein said program further comprises a step of verifying the validity of a signature SK A (I A ) from said institution A with its public key PK A  and said information I A .  
     
     
         25 . A recording medium having recorded thereon a program for execution by a computer of an institution A apparatus in a system in which a user registers different pieces of information I A  and I B  with institutions A and B, respectively, said program comprising the steps of: 
 storing said information I A  and information PK B (I B , K) from said user in a memory;    sending said information PK B (I B , K) to said institution B; and    sending information K(SK B (I B )) from said institution B to said user.    
     
     
         26 . A recording medium having recorded thereon a program for execution by a computer of an institution A apparatus in a system in which a user registers different pieces of information I A  and I B  with institutions A and B, respectively, said program comprising the steps of: 
 storing said information I A  and pieces of information K(I B ) and PK B (K) from said user in a memory;    sending said pieces of information PK B (K) and K(I B ) to said institution B; and    sending information K(SK B (I B )) from said institution B to said user.    
     
     
         27 . The recording medium of  claim 25 , wherein said memory has stored therein secret and public keys SK A  and PK A  of said institution A and said program further comprises a step of signing said information PK B (I B , K) with said secret key SK A  to obtain signature information SK A (PK B (I B , K)), said signature information SK A (PK B (I B , K)) being sent to said institution B together with said information PK B (I B , K).  
     
     
         28 . The recording medium of  claim 26 , wherein said memory has stored therein secret and public keys SK A  and PK A  of said institution A and said program further comprises a step of signing said information K(I B ) with said secret key SK A  to obtain signature information SK A (K(I B )), said signature information SK A (K(I B )) being sent to said institution B together with said pieces of information K(I B ) and PK B (K).  
     
     
         29 . The recording medium of  claim 25 ,  26 ,  27  or  28  wherein said program further comprises a step of verifying, with a public key PK B , the validity of each of said information K(SK B (I B )) and its signature SK B (K(SK B (I B ))) received from said institution B.  
     
     
         30 . The recording medium of  claim 25 ,  26 ,  27  or  28  wherein said program further comprises a step of signing said information I A  in said memory with a secret key SK A  of said institution A to generate a signature SK A (I A ), said signature SK A (I A ) being sent to said user together with said information SK B (I B ) received from said institution B.  
     
     
         31 . A recording medium having recorded thereon a program for execution by a computer of an institution B apparatus in a system in which a user registers different pieces of information I A  and I B  with institutions A and B, respectively, said program comprising the steps of: 
 deciphering information PK B (I B , K) from said institution A with a secret key SK B  to obtain said information I B  and a common cipher key K;    storing said information I B  and said common cipher key K in a memory;    signing said information I B  with said secret key SK B  to generate a signature SK B (I B );    enciphering said signature SK B (I B ) with said common cipher key K to generate information K(SK B (I B )); and    sending said information K(SK B (I B )) to said institution A.    
     
     
         32 . A recording medium having recorded thereon a program for execution by a computer of an institution B apparatus in a system in which a user registers different pieces of information I A  and I B  with institutions A and B, respectively, said program comprising the steps of: 
 deciphering information PK B (K) from said institution A with a secret key SK B  to obtain a common cipher key K;    deciphering information K(I B ) from said institution A with said common cipher key K to obtain said information I B ;    storing said deciphered information I B  and said common cipher key K in a memory;    signing said information I B  with said secret key SK B  to generate a signature SK B (I B );    enciphering said signature SK B (I B ) with said common cipher key K to generate information K(SK B (I B )); and    sending said information K(SK B (I B )) to said institution A.    
     
     
         33 . The recording medium of  claim 31 , wherein said program further comprises a step of verifying the validity of each of said information PK B (I B , K) from said institution A and its signature SK A (PK B (I B , K)) with a public key PK A  and, if they are both found valid, deciphering said information PK B (I B , K) with said secret key SK B  to obtain said information I B  and said common cipher key K.  
     
     
         34 . The recording medium of  claim 32 , wherein said program further comprises a step of verifying the validity of each of information PK B (K) from said institution A and its signature SK A (K(I B )) with a public key PK A  and, if they are both found valid, deciphering said information PK B ,(K) with said secret key SK B  to obtain said common cipher key K.  
     
     
         35 . The recording medium of  claim 31 ,  32 ,  33  or  34 , wherein said program further comprises a step of signing said information K(SK B (I B ) with said secret key SK B  to generate signature information SK B (K(SK B (I B ))), said signature information SK B (K(SK B (I B ))) being sent to said institution A together with said information K(SK B (I B )).